/*

 * Licensed to the Apache Software Foundation (ASF) under one

 * or more contributor license agreements.  See the NOTICE file

 * distributed with this work for additional information

 * regarding copyright ownership.  The ASF licenses this file

 * to you under the Apache License, Version 2.0 (the

 * "License"); you may not use this file except in compliance

 * with the License.  You may obtain a copy of the License at

 *

 *     http://www.apache.org/licenses/LICENSE-2.0

 *

 * Unless required by applicable law or agreed to in writing, software

 * distributed under the License is distributed on an "AS IS" BASIS,

 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

 * See the License for the specific language governing permissions and

 * limitations under the License.

 */

package com.bff.gaia.unified.sdk.extensions.gcp.storage;



import com.bff.gaia.unified.sdk.extensions.gcp.util.gcsfs.GcsPath;

import com.bff.gaia.unified.sdk.io.fs.ResolveOptions;

import com.bff.gaia.unified.sdk.io.fs.ResourceId;



import javax.annotation.Nullable;



import static com.bff.gaia.unified.vendor.guava.com.google.common.base.Preconditions.*;



/** {@link ResourceId} implementation for Google Cloud Storage. */

public class GcsResourceId implements ResourceId {



  private final GcsPath gcsPath;



  static GcsResourceId fromGcsPath(GcsPath gcsPath) {

    checkNotNull(gcsPath, "gcsPath");

    return new GcsResourceId(gcsPath);

  }



  private GcsResourceId(GcsPath gcsPath) {

    this.gcsPath = gcsPath;

  }



  @Override

  public GcsResourceId resolve(String other, ResolveOptions resolveOptions) {

    checkState(

        isDirectory(),

        String.format("Expected the gcsPath is a directory, but had [%s].", gcsPath));

    checkArgument(

        resolveOptions.equals(ResolveOptions.StandardResolveOptions.RESOLVE_FILE)

            || resolveOptions.equals(ResolveOptions.StandardResolveOptions.RESOLVE_DIRECTORY),

        String.format("ResolveOptions: [%s] is not supported.", resolveOptions));

    if (resolveOptions.equals(ResolveOptions.StandardResolveOptions.RESOLVE_FILE)) {

      checkArgument(

          !other.endsWith("/"), "The resolved file: [%s] should not end with '/'.", other);

      return fromGcsPath(gcsPath.resolve(other));

    } else {

      // StandardResolveOptions.RESOLVE_DIRECTORY

      if (other.endsWith("/")) {

        // other already contains the delimiter for gcs.

        // It is not recommended for callers to set the delimiter.

        // However, we consider it as a valid input.

        return fromGcsPath(gcsPath.resolve(other));

      } else {

        return fromGcsPath(gcsPath.resolve(other + "/"));

      }

    }

  }



  @Override

  public GcsResourceId getCurrentDirectory() {

    if (isDirectory()) {

      return this;

    } else {

      GcsPath parent = gcsPath.getParent();

      checkState(

          parent != null,

          String.format("Failed to get the current directory for path: [%s].", gcsPath));

      return fromGcsPath(parent);

    }

  }



  @Override

  public boolean isDirectory() {

    return gcsPath.endsWith("/");

  }



  @Override

  public String getScheme() {

    return "gs";

  }



  @Override

  @Nullable

  public String getFilename() {

    if (gcsPath.getNameCount() <= 1) {

      return null;

    } else {

      GcsPath gcsFilename = gcsPath.getFileName();

      return gcsFilename == null ? null : gcsFilename.toString();

    }

  }



  GcsPath getGcsPath() {

    return gcsPath;

  }



  @Override

  public String toString() {

    return gcsPath.toString();

  }



  @Override

  public boolean equals(Object obj) {

    if (!(obj instanceof GcsResourceId)) {

      return false;

    }

    GcsResourceId other = (GcsResourceId) obj;

    return this.gcsPath.equals(other.gcsPath);

  }



  @Override

  public int hashCode() {

    return gcsPath.hashCode();

  }

}